Blends of polyetherimide and polyester resins derived predominantly from cyclohexanedimethanol and a carbocyclic dicarboxylic acid, such as, for example, a poly(cyclohexane-dimethanol terephthalate) resin that provide improved impact strength are disclosed in U.S. Pat. No. 5,439,987. Blends of polyetherimide resins and copolyesters of terephthalic acid and/or isophthalic acid, 1,4-cyclohexanedimethanol and ethylene glycol, that is, certain poly(cyclohexane-1,4-dimethylene-co-ethylene terephthalate) resins that are said to exhibit a high flexural modulus are disclosed in U.S. Pat. No. 5,439,987.
Use of these polyetherimide-polyester blends has become prominent in areas such as microwave food containers and others where visual clarity is desired and often demanded by the consumers, and the articles formed from these blends are often subjected to significant stresses including bending such that tab-bending performance is important. This prominence is driving the need in the industry for improved blends. Consequently, polyetherimide-polyester blends that exhibit visual clarity, resistance to elevated temperature, and further improvements in thermal and hydrolytic stability, impact resistance, and tab-bending performance, are desired.